A known superconducting cable has a configuration in which a cable core is laid at the inside of a thermal insulation vacuum tube including an inner tube and an outer tube, and the cable core is cooled by flowing a cooling liquid inside the inner tube. As an example of such a superconducting cable, a configuration is described in Japanese Patent Application Laid-Open (JP-A) No. 2010-187520 in which an outer tube and a cable end section are coupled together by a bellows tube. Moreover, thermal contraction of the outer tube during cooling is absorbed by extension and contraction of the bellows tube. Moreover, a configuration in which plural cable cores are twisted together inside an inner tube is described in JP-A No. 2010-272529. Thermal contraction of the cable cores during cooling is, moreover, absorbed by the provision of slack in twisting of the cable cores.
However, the technology described in JP-A No. 2010-187520 is only disposed in the vicinity of cable end sections. Hence, thermal contraction in an intermediate portion between one cable end section and the other cable end section is not able to be absorbed, leading to cases in which load is placed on the cable. Moreover, the technology described in JP-A No. 2010-272529 proposes a configuration in which plural cable cores are provided, and therefore application is not possible to a superconducting cable provided with a single cable core, and so the technology has low versatility. Moreover, there is also room for improvement in absorbing differences in the amount of thermal contraction arising between three members, these being the cable core, the inner tube, and the outer tube.